Cascade switch with improved intermittent coupling and motive structure



Nov. 22, 1966 P. P. SCHWAB 3,287,511

CASCADE SWITCH WITH IMPROVED INTERMITTENT COUPLING AND MOTIVE STRUCTURE 2 Sheets-Sheet 1 Filed April 27, 1965 INVENTOR P/fRRE P. SCHWAB AGENT Nov. 22, 1966 P. P. SCHWAB 3,287,511

CASCADE SWITCH WITH IMPROVED INTERMITTENT COUPLING AND MOTIVE STRUCTURE Filed April 2 1965 2 Sheets-Sheet 2 OOO QOOOO OOOOO FIG. 6

FIG.

lNl ENTOR PIERRE I? SCHWAB AGENT Br X41 4 United States Patent 3,287 511 CASCADE SWITCH WITH IMPROVED INTERMIT- TENT COUPLING AND MOTIVE STRUCTURE Pierre P. Schwab,.River Edge, N.J., assignor to McGraw- Edison Company, Elgin, 11]., a corporation of Delaware Filed Apr. 27, 1965. Ser. No. 451,158 Claims. (Cl. 20014) This invention relates to a unitary switch mechanism in which a primary selector switch and a plurality of secondary selector switches are connected in a cascade arrangement.

An object of the invention is to provide a novel form of unitary switch mechanism adapted for making selective connection to a great number of output circuits within a small space.

Another object is to provide a cascade switch in which both the primary switch and the secondary switches are of the rotary type coaxially arranged and operated by a single motive means.

Another object is to provide an improved cascade switch which is of very durable construction and dependable operation.

These and other objects and features of my invention will be apparent from the following description and the appended claims.

In the description of my invention reference is had to the accompanying drawings, of which:

FIGURE 1 is a general side elevational view of the overall cascade switch mechanism according to my invention;

FIGURE 2 is a fractional sectional view taken on the line 22 of FIGURE 1 showing the primary selector switch;

FIGURE 3 is a fractional sectional view taken on the line 33 of FIGURE 1 showing one of the secondary selector switches;

FIGURE 4 is a fractional sectional view taken on the line 4-4 of FIGURE 1 Showing an odometer mechanism for driving the primary selector switch intermittently from the shaft of the secondary switches;

FIGURE 5 is a fractional sectional view taken on the line 5-5 of FIGURE 1 showing the switch detent mechanism; and

FIGURE 6 is a functional diagram of the present cascade switch and circuit arrangement.

The present cascade switch has a U-shaped frame bracket 10 onto the left arm 10:: of which is mounted a motive means preferably a rotary solenoid 11 and to the right arm 10b of which is secured a parallel frame plate 12 held by screws 13 through spacers 14 provided with threaded holes at each end. Secured to the right side of the frame plate 12 is a bank of switches including a first primary selector switch P and a plurality of secondary selector switches S of which ten switches are shown by way of example numbered respectively S to S Each of the primary and secondary switches is of the rotary selector type. The primary switch P has a rectangular switch plate 15 and each of the secondary switches have similar rectangular switch plates 16. These switch plates are made for example of a suitable insulating plastic material. The switch plates 15 and 16 are mounted in a spaced stack arrangement at the right side of the frame plate 12 through spacers 17 each having a threaded hole in one end and a threaded extension at the other end of which the firs-t spacers pass through the frame plate 12 and thread into the spacers 14 and each of the succeeding spacers 17 pass through a respective switch plate 16 and thread into the spacer ahead of it. The last switch plate 16 of the secondary switch S is secured to the preceding spacers 17 by screws 18. There are 3,287,51 l Patented Nov. 22, 1966 a CC four rows of these spacers respectively at the four corners of the switch plates to provide a rigid assembly.

Traversing the bracket arm 10b, the frame plate 12 and all of the switch plates 15 and 16 is a central common shaft 19 which has a bearing in each of these members. The switch plate 15 of the primary switch P has a set of switch contacts 20 thereon in a circular row equally spaced around the shaft 19 (FIGURE 2). Similarly, each switch plate 16 of the secondary switches S has a set of switch contacts 21 in a circular row equally spaced around the shaft 19. For example, there are forty contacts 21 of which alternate contacts are idle to provide twenty contact positions. Each active contact has a soldering lug 21a at the back side of the plate. On each switch plate 15 and 16 in concentric relation to the shaft 19 there is a slip ring 22. Mounted on the shaft 19 adjacent to the switch plate 15 is a rotor 23 and mounted on the shaft adjacent to each of the switch plates 16 is a rotor 24. Each rotor 23 and 24 has a wiper blade 25 slidably engaging the respective slip ring 22 and another wiper blade 26 slidably engaging the respective set of switch contacts. The two wiper blades are electrically interconnected so that electrical contact is made from the slip ring of a switch to the electrical contact engaged by the wiper blade 25. The rotor 23 differs from the rotor 24 only in that it has a larger hub opening receiving a sleeve shaft 27 mounted rotatably on the shaft 19.

The number of active contacts 20' on the switch plate 15 of the primary selector switch is equal preferably to the number of secondary switches S. Accordingly, there are ten active contacts 20 in the present illustrative example. The rotor 23 is advanced intermittently by one switch position for each full revolution of rotation of the shaft 19. Such intermitent movement of the rotor 23 is accomplished by means of an odometer mechanism 28 mounted on the shaft 19 between the bracket arm 10b and the frame plate 12. The odometer mechanism comprises a flanged partial gear 29 pinned to the shaft 19 and a complete gear 30 adjacent thereto which is secured to the sleeve shaft 27. The flanged gear 29 has only two regular gear teeth 29a separated by a tooth slot 29b which runs through the flange. Engaging both the flanged gear 29 and the full gear 30 is a pinion gear 31 journaled at its ends in the bracket arm 10b and frame plate 12. This pinion gear has for example eight teeth but alternate tooth portions, which are in line with the flange of the partial gear 29, are cut away as indicated at 31a (FIGURE 1). The flange of the gear 29 traverses the cutaway space 31a in a locking engagement with the pinion gear. However, when the two teeth 29a come into meshing .engagement with the pinion gear they turn the latter with one of the full teeth 31b of the pinion gear meshing with the tooth slot 29b. After such momentary turning of the pin-ion gear the flange of the partial gear 29 again engages the next cutaway space 31a in locking engagement with the pinion gear. By way of example, the full gear 30 has the same pitch diameter .as the flanged gear 29 so that a straight pinion gear can be used. Further, the full gear 30 has twice as many gear teeth as the number of secondary switches so that the two teeth of the flanged gear are capable of turning the rotor of the primary switch P by one full switch interval during each full revolution of the shaft 19. There being ten secondary switches, the full gear has therefore twenty teeth.

Since a straight pinion gear 31 is used, the coupling ratio between the shaft 19 and the sleeve shaft 27 is 1:1 during the interval that the gears 29 and 30 are engaged. Accordingly, while these gears are in coupled engagement the rotor of the primary switch P is advanced at the same rate as the rotors of the secondary switches S. However, since the primary switch P has only half as many active contacts as the respective secondary switches S the contacts 20 of the primary switch are broadened to span half the space between successive switch positions. This is done so that the primary switch P can move from one active switch con-tact to the next concurrently as the secondary switches are moved from one active contact to the next.

As shown in FIGURE 6, the contacts 20 of the primary switch are connected respectively by leads 32 to the successive slip rings of the secondary switches S to S the contact No. 1 of the primary switch being thus connected to the secondary switch S the contact No. 2 of the primary switch being connected to the secondary switch S etc. An input lead 33 is connected to the slip ring 22 of the primary switch P and output leads 34 are connected to the respective contacts of the secondary switches S to S Thus, starting with the rotor 23 in position I and the rotor 24 also in position I, and with the gears 29 and 30 having just moved out of engagement, the input lead 33 will be connected to the contact No. 1 of the secondary switch S The shaft 19 is stepped ahead via successive switch intervals from this position by the rotary solenoid 11 acting through a clutch 35. When the shaft has been stopped ahead W revolution the input circuit will be connected to contact number 19 of the secondary switch S (FIGURE 3) and the gears 29 and 30 will be starting to reen'gage. As the rotor 24 is stepped ahead to contact No. 20 (FIGURE 3) the rotor 23 is advanced to a mid-position 1t (same contact) so that a circuit is still made from the input lead 33 to the first secondary switch S As the rotor 24 is next moved one further switch interval to contact No. 1 to complete one full revolution of movement the rotor 23 is stepped ahead simultaneously to switch contact No. 2 of the primary switch P (FIGURE 2) so that the input lead 33 is now connected to the first contact of the second secondary switch S This cycle repeats at the end of each additional revolution to the shaft 19 causing the input circuit 33 to 'be transferred to the next succeeding secondary switch after each of the contacts of the next preceding secondary switch have been scanned. In view of this sequential or cascading of the switches the input circuit 33 is connected in succession to the respective contacts of the successive secondary switches and then back again to the first contact of the first secondary switch, etc., as the shaft 19 is stepped ahead by successive switch positions through successive revolutions of movement.

The rotary solenoid 11 is of a standard type having a shaft 11a which is propelled longitudinally against a cam means (not shown) to turn the shaft through a given stroke during each activation of the solenoid. The longitudinal movement of the shaft 11a is utilized to engage the normally open clutch 35. By setting the gap between the clutch plates the point during each stroke of the shaft at which the clutch is engaged is determined to select precisely the amount of rotation imparted to the switch shaft 19 during each activation of the solenoid. The setting is such that the shaft 19 is turned through one switch intervali.e., V revolutionduring each activation of the solenoid. The solenoid is activated by direct current from a DC. source 36 through a switch 37 (FIGURE 1.) Thus, each time the switch 37 is closed the clutch is engaged and the shaft 19 advanced by one switch interval and when the switch 37 is opened the solenoid drops back opening the clutch 35. A ratchet wheel 38 provided with twenty equally spaced notches is secured to the shaft 19 at the inner side of the frame arm 10b and pivoted on this frame arm is a dentent lever 39 having a roller 40 journaled thereon which engages the ratchet wheel under pressure from a tension spring 41 connected between the detent lever and a pin 42 on the frame arm 10b. (FIGURE 5). This detent mechanism operates to locate the primary .and secondary switches accurately in their respective switch positions.

The embodiment of my invention herein shown and described is intended to be illustrative and not necessarily limitative of my invention since the same is subject to changes and modifications without departure from the scope of my invention, which I endeavor to express according to the following claims.

I claim:

1. A cascade switch comprising a primary selector switch and a plurality of secondary selector switches each including a rotor and a plurality of cooperable switch contacts, said primary switch having a number of switch contacts at least as great as the number of said secondary switches and said secondary switches having identical numbers of equally spaced switch contacts, circuit means connecting the switch contacts of said primary switch respectively to the rotors of said secondary switches, stepping means for advancing in unison the rotors of said secondary switches by successive switch contact intervals through successive switch cycles, means coupled to said stepping means for advancing said primary switch from one switch contact to the next at the completion of each cycle of advance movement of said secondary switches, all of said primary and secondary switches being coaxially arranged, a common shaft for said secondary switches, a sleeve shaft for said primary switch rotatably mounted on said common shaft, and a step type coupling between said shafts for advancing said sleeve shaft from one switch contact to the next responsive to the last step advance of said common shaft in each complete revolution of movement thereof.

2. A cascade switch comprising a primary selector switch and a plurality of secondary selector switches each including a rotor, a slip ring and a set of switch contacts equally circumferentially spaced around the axis of the respective rotor, each rotor including a first wiper blade slidably engaging the respective slip ring and a second wiper blade electrically connected thereto and slidably engaging the respective switch contacts, said primary switch having as many switch contacts as the number of said secondary switches, said primary switch contacts being connected respectively to the slip rings of said secondary switches, a common shaft for said secondary switches, a sleeve shaft on said common shaft for said primary switch, a motive means operable to step said secondary switches by successive switch contact intervals through successive revolutions of rotor movement, and an intermittent coupling means between said common shaft and said sleeve shaft for advancing said primary switch from one contact to the next responsive to the last step advance of said secondary switches in each revolution of rotor movement thereof.

3. The cascade switch set forth in claim 2 wherein said respective secondary switches have a number of switch contacts which are an integral multiple of the number of contacts in said respective primary switch, wherein said intermittent coupling has a 1:1 ratio while in coupled engagement, and wherein the respective gaps between successive contacts of said primary switch are equal to the respective gaps between successive contacts of said respective secondary switches.

4. The cascade switch set forth in claim 2 wherein said intermittent coupling means comprises an odometer mechanism including a full gear connected to said sleeve shaft having twice the number of teeth as the number of said secondary switches, a partial gear of the same diameter as said full gear connected to said common shaft and having a peripheral flange of the diameter of said full gear and two teeth integral with said flange and having the tooth slot therebetween running through said flange, and a pinion gear extending past said two gears on an axis parallel to said shaft and having alternate tooth portions removed in line with said flange whereby each revolution of said partial gear advances said full gear by two tooth intervals during a portion of each revolution of said common shaft and locks said full gear during the remaining portion of each revolution responsive to the engagement of said flange with the respective spaces in said coupling gear provided by the cutaway of said alternate teeth.

5. The cascade switch set forth in claim 2 including a notched wheel connected to said common shaft and having a number of teeth equal to the number of switch contact positions in said respective secondary switches, and a pawl yieldably engaging said notched wheel to detent said secondary switches in their respective switch positions.

References Cited by the Examiner UNITED STATES PATENTS 2,788,408 4/57 Cheney 20017 XR 2,811,594 10/57 Papouschek 200l4 3,098,129 7/63 Lynch et al 200-1l 3,214,531 10/65 Dux 20014 X ROBERT K. SCHAEFER, Primary Examiner.

10 J. R. SCOTT, Assistant Examiner. 

1. A CASCADE SWITCH COMPRISING A PRIMAY SELECTOR SWITCH AND A PLURALITY OF SECONDARY SELECTOR SWITCHES EACH INCLUDING A ROTOR AND A PLURALITY OF COOPERABLE SWITCH CONTACTS, SAID PRIMARY SWITCH HAVING A NUMBER OF SWITCH CONTACTS AT LEAST AS GREAT AS THE NUMBER OF SAID SECONDARY SWITCHES AND SAID SECONDARY SWITCHES HAVING IDENTICAL NUMBERS OF EQUALLY SPACED SWITCH CONTACTS, CIRCUIT MEANS CONNECTING THE SWITCH CONTACTS OF SAID PRIMARY SWITCH RESPECTIVELY TO THE ROTORS OF SAID SECONDARY SWITCHES, STEPPING MEANS FOR ADVANCING IN UNISON THE ROTORS OF SAID SECONDARY SWITCHES BY SUCCESSIVE SWITCH CONTACT INTERVALS THROUGH SUCCESSIVE SWITCH CYCLES, MEANS COUPLED TO SAID STEPPING MEANS FOR ADVANCING SAID PRIMARY SWITCH FROM ONE SWITCH CONTACT TO THE NEXT AT THE COMPLETION OF EACH CYCLE OF ADVANCE MOVEMENT OF SAID SECONDARY SWITCHES, ALL OF SAID PRIMARY AND SECONDARY SWITCHES BIENG COAXIALLY ARRANGED, A COMMON SHAFT FOR SAID SECONDARY SWITCHES, A SLEEVE SHAFT FOR SAID PRIMARY SWITCH ROTATABLY MOUNTED ON SAID COMMON SHAFT, AND A STEP TYPE COUPLING BETWEEN SAID SHAFTS FOR ADVANCING SAID SLEEVE SHAFT FROM ONE SWITCH CONTACT TO THE NEXT RESPONSIVE TO THE LAST STEP ADVANCE OF SAID COMMON SHAFT IN EACH COMPLETE REVOLUTION OF MOVEMENT THEREOF. 